1. Field of the Invention
The present invention relates to quality control of seismic data processing. Specifically, the present invention involves computerized evaluation of seismic data processing software for suppression and removal of multiple reflections or multiples.
2. Description of the Related Art
Multiple reflections, or multiples, are present in the results of virtually every seismic exploration survey. They are, however, undesirable since their presence can mask or interfere with the meaningful reflections, known as primary reflections or primaries, which are of interest in geophysical exploration. Presently available seismic data processing software usually includes some form of multiple-suppression software.
Multiple-suppression software has generally attempted to identify and remove multiple reflections from seismic data, while simultaneously preserving primary reflections. Multiple suppression has been one of the classic geophysical problems, and there have been many different approaches, each generally optimized for a specific type of multiple (e.g., water-bottom, interbed, short-period, and the like). The effectiveness of any particular multiple-suppression method was generally data-dependent. Also, since approximations varied, different implementations of an algorithm have performed differently. This has made it difficult for users to quantify the accuracy of any particular type or set multiple-suppression software.
So far as is known, multiple-suppression software has generally been tested by creating synthetic data from a known earth model, processing these data with some multiple-suppression software, and visually examining the results. This approach was largely qualitative, allowing different observers to reach different conclusions. This approach also did not quantify how well multiples were suppressed and how well primaries were preserved. Also, when the synthetic data contained many primary and multiple reflections, the data displays would often become quite cluttered or "busy," revealing little helpful information for evaluation purposes during visual examination.